1. Field of the Invention
The invention relates generally to an eyeglass frame that allows the lenses to be changed and more particularly to an eyeglass frame that allows the wearer to change lenses without use of special apparatus or the help of opticians.
2. Description of the Prior Art
Conventional eyeglasses generally fall into two main types: optical glasses and sunglasses. In optical glasses, the lenses are fixedly mounted in the rims. Likewise, lenses of sunglasses are fixedly mounted, and sunglasses are not suitable for wearing indoors as they block the light. In mounting lenses on a thermoplastic frame, the frame is heated in a heating apparatus so that the rims expand to allow insertion of the lenses. Such cannot be done by the wearer bare-handedly. Fixing lenses in metal frames also requires tools to tighten the tiny screws.
FIG. 1 shows a conventional eyeglass frame that basically comprises a from 1 and temples 3 connected to either end of the front 1. The front 1 is heated in a heating apparatus so that its rims 2 expand to allow mounting of two lenses 4 therein respectively. When the rims 2 are cool and contact, the lenses 4 will be secured therein. In a metallic frame, the front 1 is formed to consist of an upper portion and a lower portion. Lenses 4 are placed inside the rims 2 and the upper and lower portions are joined by tiny screws. Neither of the above methods of mounting the lenses 4 can be done by the wearer without any tools. Thermoplastic frames may easily deform in shape so that the lenses may drop out. For metallic frames, the tiny screws may crack and cannot be removed from the screw holes so that the lenses cannot be firmly secured or the frame cannot be used again.
A user may need to change glasses anytime and he/she has to prepare several pairs of eyeglasses with lenses of different shades or for different purposes, which is very inconvenient.